Folic acid and folate in foods
Our bodies need a steady supply of what used to be known as vitamin B9. It comes in several forms. In food, it's called folate. A synthetic form, folic acid, is added to some foods and used as an ingredient in vitamin supplements. The body absorbs folic acid faster than it absorbs folate. But folic acid must then be converted into folate before it can get to work.
When referring to the amounts of these in food, the USDA relies on what it calls dietary folate equivalents (DFE). The DFE of a food equals the amount contributed by folate naturally in the food plus 1.7 times the times the amount of added folic acid. In the USDA's list of folate in foods, it uses the DFE to rank foods, putting breakfast cereals and other fortified foods near the top. Here's a list of foods naturally rich in folate.